Tuyere



Aug. 25, 1942. W.A. RIDDELL TUYERE Filed Dec. 18, 1940 Patented Aug. 25, 1942 UNITED STATES OFFICE 2,293,921 TUYERE William A. Riddell, Frederick, Md.

Application December 18, 1940, Serial No. 370,660

4 Claims.

This invention relates to improvements in tuyre plate construction for use in connection with multiple-retort underfeed stoker furnaces, and the primary object is to provide a tuyere plate of such design as to cooperate'with corresponding and adjacent plates in more efliciently controlling the air passage therebetween. More specifically the object is to provide such a tuyre plate with a depending arcuate rib that is integrally formed with the plate and is so arranged with reference to an air inlet opening of an adjacent plate as to create an air turbulence, which in turn is found to more effectively cool the exposed plate surfaces while also supplying the air in proper distribution to effect uniform combustion in the fuel bed.

In the accompanying drawing, which illustrates a preferred embodiment of the invention Fig. l is a plan view of three superimposed tuyre plates of a row such as is conventionally arranged in a retort or furnace, the uppermost of said plates being shown, partly in section as on the line ll in Fig. 2.

Fig. 2 is a longitudinal sectional elevation through the three tuyre plates, as on line 2-2 in Fig. 1.

Referring tothe drawing more particularly and by reference numerals, 3 designates the tuyere plate, a series of which are superimposed one upon the other and in offset relation so as to form an inclined fuel bed support, and the forward upper surfaces of which are preferably sloped, as at 4, to facilitate the progressive movement of the fuel thereover. The forward or nose ends of the plates are supported in spaced relation one upon the other by a plurality of fins or ribs 5, disposed in generally radial or diverging arrangement, and have for their purpose to distribute the air for combustion over a fan shaped area and in a confined vertical space between the tuyre plates. These ribs, as shown, are integral with and depend from the upper plate of each air space and rest with their lower edges upon the adjacent lower plate.

Each plate is also provided with a depending integrally formed lock hook 6 which extends through an aperture 1 in the plate immediately below it to thereby releasably lock the plates of each series together, but which will also permit quick and easy removal of the plates as they ultimately disintegrate or burn out sufficiently to require replacement.

At its rear end each plate 3 has an inwardly curved edge 8 forming an air induction recess 9, and forwardly of such recess each plate is also provided with a depending flange or rib H], which is curved in a direction reverse to the curvature of the edge 8. At its ends the rib l0 terminates in side Wall lugs II which operate to restrict the air fiow and to support the respective plates upon each other.

It will be noted, with particular reference to Fig. 2, that each rib I0 is so disposed that it passes over the recess 9, so as to limit the crosssectional area of the aperture through which the air must pass from the air box, in the rear, to the air chambers or spaces between the plates; and by adjusting the fore and aft position of the rib, in the casting pattern, the size of this aperture can be adjusted or predetermined to conform with the requirements of particular furnace conditions and capacities.

The rib I0 is found to cooperate with the aperture 9 in producing a combination venturi and valve action whereby a sufficient volume of air is admitted to support combustion without necessitating direct or excessively high pressures. It is also found that the position and form of the rib I0 is such as to intercept and divert the normal air flow, thus creating an air turbulence that has maximum cooling effect on the plate surfaces, while also producing uniform distribution of air flow to the spaces between the ribs 5. It will of course be understood that while the curved rib I0 has a tendency to retard the air fiow through aperture 9, and thereby also lowers the air pressure between the plates, it will not interfere with the building up of such pressure when, for instance, there have been increases or variations in the depth of the fuel bed or other conditions tending to clog the air openings to the fuel bed through the nose ends of the tuyeres.

It is understood that suitable modifications may be made in the structure as disclosed, provided such modifications come within the spirit and scope of the appended claims. Having now therefore fully illustrated and described my invention, what I claim to be new and desire to protect by Letters Patent is:

1. In combination at least two tuyre plates arranged in vertically spaced relation to form a chamber for the horizontal forward passage of air therebetween, one of said plates having an air recess at its rear and the other plate having a transversely disposed flange member forming the rear limit of said chamber and extending across the recess to limit the opening thereof and control the air passage therethrough, said flange member being so disposed as to deflect the air flow through said chamber and thereby produce a turbulence in the air flow.

2. In combination, at least two vertically spaced horizontally disposed tuyere plates, one of said plates having a recess extending in from its rear edge, and the other of said plates having a rib extending across said recess and complementing the forward edge thereof to define an aperture for the flow of air into and forwardly through the space between the plates.

3. In combination, at least two vertically spaced horizontally disposed tuyre plates, one of said plates having a recess extending in from its rear edge, and the other of said plates having a rib extending across said recess to define an aperture for an air flow into the space between the tuyres, said rib extending entirely across the plate and terminating at its ends in side wall lug extensions of the plate.

4. A pair of similarly formed tuyre plates each having a recess in its rear end and a depending fiange extending generally transversely of the plate forwardly of the recess, said flange and. recess of each plate being so positioned with respect to each other that the flange of one plate will traverse the recess of the other plate to form an air passage aperture, when such plates are mounted one upon the other and in predetermined rearwardly offset relationship.

WILLIAM A. RIDDELL. 

